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Solar Eruption Mistaken for Refueling UFO Spaceship

Copyright NASA

Telescope images captured of the sun on Monday (March 12) show what appears to be a planet-size shadowy object tethered to the sun by a dark filament. In the image sequence, a burst of brightly lit material can be seen erupting from the sun’s surface surrounding the dark object, after which the orb detaches from the sun and shoots out into space.

The footage, a composite of images captured by the Solar Dynamics Observatory and processed by scientists at NASA’s Goddard Space Flight Center, has quickly garnered attention on YouTube, where viewers are suggesting it shows a UFO spacecraft refueling by sucking up solar plasma, or at the very least, the birth of a new planet.

However, according to NASA scientists, the feature is actually a little-understood, but frequently observed, type of solar activity called a “prominence,” and the way it is situated beneath another solar feature gives it its otherworldy appearance.

Mars Express radar gives strong evidence for former Mars ocean

Mars Express radar gives strong evidence for former Mars ocean

Copyright ESA

ESA’s Mars Express has returned strong evidence for an ocean once covering part of Mars. Using radar, it has detected sediments reminiscent of an ocean floor within the boundaries of previously identified, ancient shorelines on Mars.

The MARSIS radar was deployed in 2005 and has been collecting data ever since. Jérémie Mouginot, Institut de Planétologie et d’Astrophysique de Grenoble (IPAG) and the University of California, Irvine, and colleagues have analysed more than two years of data and found that the northern plains are covered in low-density material. “We interpret these as sedimentary deposits, maybe ice-rich,” says Dr Mouginot. “It is a strong new indication that there was once an ocean here.”

The existence of oceans on ancient Mars has been suspected before and features reminiscent of shorelines have been tentatively identified in images from various spacecraft. But it remains a controversial issue.

Two oceans have been proposed: 4 billion years ago, when warmer conditions prevailed, and also 3 billion years ago when subsurface ice melted, possibly as a result of enhanced geothermal activity, creating outflow channels that drained the water into areas of low elevation.

Mars Express radar investigation “MARSIS penetrates deep into the ground, revealing [...]

Neighbouring volcanoes on Mars

Copyright ESA

ESA’s Mars Express has returned images of mist-capped volcanoes located in the northern hemisphere of the red planet. Long after volcanic activity ceased, the area was transformed by meteor impacts that deposited ejected material over the lower flanks of the volcanoes.

Permanent and transient features are on display in this newly released image of Mars. The image is derived from data acquired during three orbits of ESA’s Mars Express between 25 November 2004 and 22 June 2006. In that time, these dead volcanoes were not expected to change but, during the middle orbit, Mars Express captured icy clouds drifting past the summit of Ceraunius Tholus.

By the time Mars Express crossed again and took the final strip of data needed for this image, the clouds had long since dispersed and so there is a sharp line across them in the finished mosaic.

The Latin word “tholus” means a conical dome and the base of Ceraunius Tholus is 130 km across, while the peak rises 5.5 km above the surrounding plains. At its summit is a large caldera 25 km across. With similar morphology to its neighbour and lying 60 km to the north, Uranius Tholus is [...]

Mars Express close flybys of martian moon Phobos

Copyright ESA

Mars Express has returned images from the Phobos flyby of 9 January 2011. Mars Express passed Mars’ largest moon at a distance of 100km.

LRO Creating Unprecedented Topographic Map of Moon

Copyright NASA

“This dataset is being used to make digital elevation and terrain maps that will be a fundamental reference for future scientific and human exploration missions to the moon,” said Dr. Gregory Neumann of NASA’s Goddard Space Flight Center in Greenbelt, Md. “After about one year taking data, we already have nearly 3 billion data points from the Lunar Orbiter Laser Altimeter on board the LRO spacecraft, with near-uniform longitudinal coverage. We expect to continue to make measurements at this rate through the next two years of the science phase of the mission and beyond. Near the poles, we expect to provide near-GPS-like navigational capability as coverage is denser due to the spacecraft’s polar orbit.” Neumann will present the map at the American Geophysical Union meeting in San Francisco December 17.

The Lunar Orbiter Laser Altimeter (LOLA) works by propagating a single laser pulse through a Diffractive Optical Element that splits it into five beams. These beams then strike and are backscattered from the lunar surface. From the return pulse, the LOLA electronics determines the time of flight which, accounting for the speed of light, provides a precise measurement of the range from the spacecraft to the lunar [...]

Light and dark in the Phoenix Lake

Copyright ESA

They say you can’t judge a book by its cover but, with planets, first impressions do count. New images show where complex fault lines in Mars’ Phoenicis Lacus region have resulted in terrain with a distinctly contrasting appearance.

Nineteenth-century astronomers were the first to see Phoenicis Lacus on Mars. They identified it as a dark spot, and thought that it resembled a sea. Now we know that it is not a body of water but the southwestern extension of the complex Noctis Labyrinthus system, which stretches away from the giant volcanoes of Mars’s Tharsis region.

The brightness of a surface feature is still the first thing planetary astronomers notice. It is known as the albedo and is partly determined by the composition of the surface material. For example, ice is more reflective than rock. The texture of the surface also plays a part, with rough surfaces reflecting less sunlight and so appearing darker than smooth surfaces.

Phoenicis Lacus has an area of 8100 sq km (59.5 x 136 km), which corresponds to the size of Corsica. Only a small portion of it appears in this image, which was obtained on 31 July 2010 using the [...]

Study Links Fresh Mars Gullies to Carbon Dioxide

Copyright NASA

A growing bounty of images from NASA’s Mars Reconnaissance Orbiter reveals that the timing of new activity in one type of the enigmatic gullies on Mars implicates carbon-dioxide frost, rather than water, as the agent causing fresh flows of sand.

Researchers have tracked changes in gullies on faces of sand dunes in seven locations on southern Mars. The periods when changes occurred, as determined by comparisons of before-and-after images, overlapped in all cases with the known winter build-up of carbon-dioxide frost on the dunes. Before-and-after pairs that covered periods only in spring, summer and autumn showed no new activity in those seasons.

“Gullies that look like this on Earth are caused by flowing water, but Mars is a different planet with its own mysteries,” said Serina Diniega, lead author of a report on these findings in the November issue of the journal Geology. She analyzed these gullies while a graduate student at the University of Arizona, Tucson, and recently joined NASA’s Jet Propulsion Laboratory, Pasadena. “The timing we see points to carbon dioxide, and if the mechanism is linked to carbon-dioxide frost at these dune gullies, the same could be true for other gullies on Mars.”

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A Snapshot of Sea Ice

Copyright NASA

How does the Aqua satellite “see” sea ice? Microwaves. Everything on Earth’s surface — including people — emits microwave radiation, the properties of which vary with the emitter, thereby allowing the AMSR-E microwave sensor on Aqua to map the planet.

Ice emits more microwave radiation than water, making regions of the ocean with floating ice appear much brighter than the open ocean to the AMSR-E sensor. This difference allows the satellite to capture a sea ice record year-round, through cloud cover and the months of polar night. Continuous records are important because sea ice is dynamic. Besides melting and freezing, the ice moves with wind and currents which can cause it to split or pile up.

“The data from AMSR-E and other NASA satellites are critical for understanding the coupling between sea ice and the ocean and atmosphere,” said Tom Wagner, Cryosphere program manager at NASA Headquarters in Washington. “It’s important for us to understand these connections to improve our predictive models of how the planet will change.”

The Arctic sea ice is a major factor in the global climate system. The ice cools the planet by reflecting sunlight back into space. It also helps drive ocean [...]

NASA Data Shed New Light About Water and Volcanoes on Mars

Copyright NASA

Data from NASA’s Phoenix Mars Lander suggest liquid water has interacted with the Martian surface throughout the planet’s history and into modern times. The research also provides new evidence that volcanic activity has persisted on the Red Planet into geologically recent times, several million years ago.

Although the lander, which arrived on Mars on May 25, 2008, is no longer operating, NASA scientists continue to analyze data gathered from that mission. These recent findings are based on data about the planet’s carbon dioxide, which makes up about 95 percent of the Martian atmosphere.

“Atmospheric carbon dioxide is like a chemical spy,” said Paul Niles, a space scientist at NASA’s Johnson Space Center in Houston. “It infiltrates every part of the surface of Mars and can indicate the presence of water and its history.”

Phoenix precisely measured isotopes of carbon and oxygen in the carbon dioxide of the Martian atmosphere. Isotopes are variants of the same element with different atomic weights. Niles is lead author of a paper about the findings published in Thursday’s online edition of the journal Science. The paper explains the ratios of stable isotopes and their implications for the history of Martian water and [...]

Missing Piece Inspires New Look at Mars Puzzle

Copyright NASA

Experiments prompted by a 2008 surprise from NASA’s Phoenix Mars Lander suggest that soil examined by NASA’s Viking Mars landers in 1976 may have contained carbon-based chemical building blocks of life.

“This doesn’t say anything about the question of whether or not life has existed on Mars, but it could make a big difference in how we look for evidence to answer that question,” said Chris McKay of NASA’s Ames Research Center, Moffett Field, Calif. McKay coauthored a study published online by the Journal of Geophysical Research – Planets, reanalyzing results of Viking’s tests for organic chemicals in Martian soil.

The only organic chemicals identified when the Viking landers heated samples of Martian soil were chloromethane and dichloromethane — chlorine compounds interpreted at the time as likely contaminants from cleaning fluids. But those chemicals are exactly what the new study found when a little perchlorate — the surprise finding from Phoenix — was added to desert soil from Chile containing organics and analyzed in the manner of the Viking tests.

“Our results suggest that not only organics, but also perchlorate, may have been present in the soil at both Viking landing sites,” said the study’s lead author, [...]